$OpenBSD: patch-backend_snapscan-usb_c,v 1.1 2016/05/18 20:02:27 sthen Exp $

errno.h header is required now that errno is a per-thread variable.
"undefined symbol 'errno'" at runtime with dlopen()'d modules.

--- backend/snapscan-usb.c.orig	Sat Feb 23 02:00:56 2013
+++ backend/snapscan-usb.c	Wed May 18 14:02:25 2016
@@ -73,6 +73,7 @@
 
 #include "snapscan-usb.h"
 #include "snapscan-mutex.c"
+#include <errno.h>
 
 #ifndef SHM_R
 #define SHM_R 0
